The present invention is generally directed to a robotic apparatus and, more particularly, to a remotely controlled robotic apparatus adapted to travel through enclosed spaces such as pipes or ducts using mechanically enabled inchworm-like motions.
The use of robotic devices and particularly robotic vehicles has become increasingly important in recent years as researchers seek to develop new and improved methods for carrying out remote or hazardous tasks with minimal human effort. A wide variety of tasks are envisioned for robotic devices.
For example, search-and-rescue, damage assessment and other information-gathering operations could be carried out by robotic vehicles at sites such as a buildings damaged by earthquakes or bombings. When rescuers and members of disaster teams approach a collapsed building or other structure, they face the difficulty of trying to rescue the survivors they have located without accidentally injuring those they have not yet found. In the rubble of a large building, it is difficult to know where survivors are trapped and rescuers sometimes risk their own lives climbing into the rubble to find the survivors. Because pipes and other enclosed conduits are often left intact when buildings collapse, a robotic vehicle could be used to navigate the pipes in order to move through the buildings. Similarly, robotic vehicles could be employed in hostage situations to travel through HVAC ductwork or plumbing systems in order to gather intelligence on the terrorists and their hostage victims. In other examples, robotic vehicles could be used to perform inspection and maintenance tasks, and to carry out non-destructive testing, in remote or hazardous locations such as nuclear power plant pipes and gas or water lines.
In performing any of the foregoing tasks, the design of the robotic vehicle should permit a number of different kinds of instruments and sensors to be installed thereon. For example, accelerometers could be used to detect vibrations made by a survivor""s tapping on pipes. Speakers could be used to output music or messages to provide comfort and information to victims. Microphones could be used to pick-up various informative sounds within a building or the conduit of the building through which the robotic vehicle travels. Video cameras could be used to enable the operators of the robotic apparatus to detect cracks or scaling in a pipe, or to view the area outside the end of a conduit such as by viewing a room from the vantage point of a vent. Video cameras could also be used to assist maintenance personnel in mapping out the layout of an unknown system of pipes or ducts. Other sensors include infrared sensors to detect heat, chemical monitors such as electronic noses to detect gas leaks or oxygen or pH concentration, tactile sensors, radioactivity sensors, and the like. Instruments include sampling devices, gripping devices, manipulative arms, and other task-specific tools. In one example, a robotic vehicle equipped with a gripping device could be used to pull the ends of wires and cables through a length of electrical conduit.
Various robotic vehicular devices have heretofore been developed. U.S. Pat. Nos. 5,293,823 and 5,497,707 to Box disclose a robotic apparatus wherein inflatable bladders are used to engage the inside surface of a pipe and three tubular bellows are used to move and turn the robotic apparatus through the pipe. U.S. Pat. Nos. 5,601,025 and 5,791,255 to Box disclose a robotic apparatus wherein radially extendable shoes and pivotable arcuate arms are actuated by pistons to engage the inside surface of a pipe. U.S. Pat. No. 5,121,694 to Zollinger discloses a robotic apparatus wherein air cylinders are used to expand and contract its length and to extend and retract leg members to engage the inside surface of a pipe. U.S. Pat. No.5,018,451 to Hapstack also discloses a robotic apparatus wherein air cylinders are used to expand and contract its length and to extend and retract legs for engaging the inside surface of a pipe. U.S. Pat. Nos. 5,080,020; 4,938,081 and 4,848,168 to Negishi disclose a robotic apparatus wherein inflatable elastic elements are used to expand and contract the robotic apparatus and engage the inside surface of a pipe. U.S. Pat. No. 4,770,105 to Takagi et al. discloses a robotic apparatus wherein motor-driven continuous treads are used to engage the inside surface of a pipe and move the robotic apparatus therethrough. U.S. Pat. No. 4,862,808 to Hedgcoxe et al. discloses a robotic apparatus using a combination of motor-driven and idler wheels to engage the inside surface of a pipe and transport the robotic apparatus therethrough.
In Micro Inspection Robot for 1-in. Pipes, IEEE/ASME TRANSACTIONS ON MECHATRONICS, Vol. 4, No. 3, September 1999, Suzumori et al. disclose a robotic apparatus using electromagnetic motor-driven planetary gear and wheel assemblies to engage the inside surface of a pipe and transport the robotic apparatus therethrough. Robotic devices employing inchworm-like or snake-like motion in endoscopic or other miniaturized applications are disclosed in U.S. Pat. No. 5,386,741 to Rennex; U.S. Pat. No. 5,906,491 to Dario et al.: and in an IEEE publication entitled Characteristics of Piezoelectric Locomotive Mechanism foran In-Pipe Micro Inspection Machine, SIXTH INTERNATIONAL SYMPOSIUM ON MICRO MACHINE AND HUMAN SCIENCE, 1995, by Idogaki. Other robotic-like devices adapted to move through pipes are disclosed in U.S. Pat. Nos. 5,574,347 to Newbauer and U.S. Pat. No. 6,026,911 to Angle et al.
Factors such as complexity, efficiency and practicality are some of the impediments to developing robotic solutions that can lead to general acceptance within a given industry. The present invention is a development in the field of biorobotics, which generally is a study of advanced robotics based on biological or physiological models. The biorobotic approach considers that biological and physiological models offer appropriate directions for inquiry by mankind, since such models have been selected, developed and tested by natural mechanisms over great spans of time. The challenge rests in emulating such models in the form of man-made implementations, while at the same time preventing such implementations from becoming so mechanically complex or energy-dependent that insufficient practicality and utility results therefrom.
Accordingly, the present invention finds a solution in the mechanical emulation of the crawling motion of an inchworm or caterpillar. While some of the robotic devices disclosed in the above-cited references emulate inchworm-like motion, it is acknowledged by those skilled in the art that there is much room for further improvement. The present invention is considered as providing an efficient, simplified and practicable solution to the problems associated with robotic vehicles designed to traverse enclosed spaces.
The present invention provides a robot adapted to crawl through pipes by performing inchworm or caterpillar-like movements. Moreover, the robot is adapted to crawl in both forward and reverse directions as well as along horizontal, sloped and vertical planes. Still further, the robot is adapted to maneuver right-angle turns, not only by turning left or right in the horizontal plane but also by turning up or down between horizontal and vertical planes.
Accordingly, the present invention provides a robotic apparatus adapted for locomotion in an enclosed space comprising a front segment, a medial segment, and a rear segment. The front segment includes a front work-energy transfer device mounted thereto in operative communication with a power supply source. A plurality of front radial displacement members extend radially outwardly with respect to the front segment. A plurality of front gripping members are also included. Each front gripping member is attached to a corresponding one of the plurality of front radial displacement members. A front mechanical linkage interconnects the front work-energy transfer device and each front radial displacement member in order to translate axial motion of the front work-energy transfer device into radial motion of each front radial displacement member.
The medial segment includes first and second medial work-energy transfer devices mounted thereto in operative communication with the power supply source. The first medial work-energy transfer device includes a first axial translation member. The second medial work-energy transfer device includes a second axial translation member disposed in opposing axial relation to the first axial translation member in order to enable expansion and contraction of an overall length of the medial segment.
The rear segment includes a rear work-energy transfer device mounted thereto in operative communication with the power supply source. A plurality of rear radial displacement members extend radially outwardly with respect to the rear segment. The rear segment also includes a plurality of rear gripping members, each rear gripping member being attached to a corresponding one of the plurality of rear radial displacement members. A rear mechanical linkage interconnects the rear work-transfer device and each rear radial displacement member in order to translate axial motion of the rear work-energy transfer device into radial motion of each rear radial displacement member. A first flexible coupling interconnects the front segment and the first axial translation member of the medial segment, and a second flexible coupling interconnects the second axial translation member of the medial segment and the rear segment.
In another embodiment according to the present invention, a robotic apparatus adapted for locomotion in an enclosed space comprises a plurality of leveraging segments and a plurality of locomotive segments. Each leveraging segment includes a leveraging segment work-energy transfer device mounted thereto in operative communication with a power supply source. A plurality of radial displacement members extend radially outwardly with respect to the leveraging segment. Each leveraging segment also includes a plurality of gripping members, each gripping member being attached to a corresponding one of the plurality of radial displacement members. A mechanical linkage interconnects the leveraging segment work-energy transfer device and each radial displacement member in order to translate axial motion of the leveraging segment work-energy transfer device into radial motion of each radial displacement member. Each locomotive segment includes first and second locomotive segment work-energy transfer devices mounted thereto in operative communication with the power supply source. The first locomotive segment work-energy transfer device includes a first displacement member. The second locomotive segment work-energy transfer device includes a second displacement member disposed in opposing axial relation to the first displacement member in order to enable expansion and contraction of an overall length of the medial segment. A plurality of flexible couplings interconnect the leveraging segments and the first and second displacement members of the locomotive segments.
In a further embodiment according to the present invention, a robotic apparatus adapted for locomotion in an enclosed space comprises a front segment, a medial segment, and a rear segment. The front segment includes a front frame and a front work-energy transfer device mounted to the front frame in operative communication with a power supply source. The front work-energy transfer device includes a front displacement member. A plurality of front leg members extend radially outwardly with respect to a central longitudinal axis of the front segment. The front segment also includes a plurality of front foot members. Each front foot member includes a frictional surface and is attached to a corresponding one of the plurality of front leg members. A front mechanical linkage interconnects the front displacement member and each front leg member in order to translate axial motion of the front displacement member into radial motion of each front leg member.
The medial segment includes a medial frame and first and second medial work-energy transfer devices mounted to the medial frame in operative communication with the power supply source. The first medial work-energy device includes a first medial displacement member, and the second medial work-energy transfer device includes a second medial displacement member. A first flexible coupling interconnects the front segment and the medial segment.
The rear segment includes a rearframe and a rear work-energy transfer device mounted to the rear frame In operative communication with the power supply source. The rear work-energy transfer device includes a rear displacement member. A plurality of rear leg members extend radially outwardly with respect to a central longitudinal axis of the rear segment. The rear segment also includes a plurality of rear foot members. Each rear foot member includes a frictional surface and is attached to a corresponding one of the plurality of rear leg members. A rear mechanical linkage interconnects the rear displacement and each rear leg member in order to translate axial motion of the rear displacement member into radial motion of each rear leg member. A second flexible coupling interconnects the medial segment and the rear segment.
The present invention also provides a system for controlling locomotion of a robotic apparatus through an enclosed space. The system comprises an actuation power supply source, a robotic apparatus, and first and second control modules. The robotic apparatus includes at least two gripping modules and a locomotive module interconnecting the gripping modules. Each gripping module includes a gripping power transfer device communicating with the actuation power supply source, a plurality of radially disposed reciprocative gripping members, and a mechanical linkage interconnecting the gripping power transfer device and the gripping members. Each locomotive module includes one or more locomotive power transfer devices communicating with the actuation power supply source. The locomotive power transfer device operates to alternately expand and contract an overall length of the locomotive module. The first control module controls a flow of an actuation power medium from the actuation power supply source to the gripping and locomotive power transfer devices. The second control module controls an operational sequence of the gripping and locomotive power transfer devices. The first control module is responsive to signals communicated thereto from the second control module.
The present invention additionally provides a method for enabling a robotic apparatus to travel through an enclosed space. In this method, a robotic apparatus is provided with front and rear gripping modules, a locomotive module, a first flexible coupling interconnecting the front gripping module and the locomotive module, and a second flexible coupling interconnecting the rear gripping module and the locomotive module. The front gripping module is provided with a plurality of radially disposed front gripping members powered by an actuation power supply source, and the rear gripping module is provided with a plurality of radially disposed rear gripping members powered by an actuation power supply source. The locomotive module is provided with a reciprocative assembly powered by the actuation power supply source. The robotic apparatus is caused to execute a sequence of actuating steps. As part of these actuating steps, each of the front and rear gripping members is caused to alternately extend and retract. In addition, the reciprocative assembly is caused to alternately expand and contract an overall length of the locomotive module in order to increase and decrease respective overall distances between the locomotive module and the front gripping module and between the locomotive module and the rear gripping module.
The present invention also provides a computer program product comprising computer-executable instructions embodied in a computer-readable medium for performing the following steps. A front gripping mechanism of a robotic apparatus is caused to alternately extend and retract in order to engage and disengage the robotic apparatus with a wall of an enclosed space. A rear gripping mechanism of the robotic apparatus is caused to alternately extend and retract to engage and disengage the robotic apparatus with the wall of the enclosed space. A reciprocative assembly of the robotic apparatus is caused to alternately expand and contract an overall length of the robotic apparatus whereby the robotic apparatus crawls through the enclosed space.
In the present invention, it is preferred that the work-energy transfer devices take the form of pneumatic actuators powered by compressed air. The use of compressed air as a power medium is useful when it is desired to avoid stray sparks that could ignite flammable substances, explosive gases or other combustibles in the environment.
The modular nature of the robotic apparatus according to the present invention permits a variety of instruments and sensors to be added thereto. Such instruments and sensors can be mounted to various locations on the segments or framework of the robotic apparatus, or can be included as part of a nose module mounted to the front segment.
Accordingly, it is an object of the present invention to provide a robotic apparatus capable of traveling through enclosed spaces such as pipes and ductwork.
It is another object of the present invention to provide a robotic apparatus capable of traveling through inclined and even vertical courses of enclosed spaces, and capable of maneuvering through turns in such courses.
It is a further object of the present invention to provide a robotic apparatus characterized by a modular design such that a number of enclosure-gripping, locomotive, sensing and instrumental modules can be selected for incorporation into the robotic apparatus, and can be easily added to or removed from the robotic apparatus as well as interchanged with other modules of the robotic apparatus.
It is yet another object of the present invention to provide a robotic apparatus characterized by a relatively simple mechanical design such that the risk of operational failure during critical tasks of the robotic apparatus is minimized.
It is a still further object of the present invention to provide a robotic apparatus adapted to crawl through an enclosed space in an inchworm-like motion by translating axial actuating motion into radial actuating motion.
It is an additional object of the present invention to provide a robotic apparatus whose motion and operations can be remotely controlled by a user through the use of a tether or umbilical line.
Some of the objects of the invention having been stated hereinabove, other objects will become evident as the description proceeds when taken in connection with the accompanying drawings as best described hereinbelow.